JPH02143251A - Damping-waterless photosensitive planographic printing plate - Google Patents

Abstract

PURPOSE:To obtain the planographic printing plate which can be easily produced and has a good coating property by incorporating a polymer having a polyorganosiloxane unit in the side chain into an ink repulsive layer and photosensitive layer. CONSTITUTION:The graft polymer having the polyorganosiloxane unit in the side chain (branch polymer) is used for the ink repulsive layer and the graft polymer having the polyorganosiloxane unit in the side chain is incorporated into the photosensitive layer as well. Namely, the ink repulsive layer and the photosensitive layer contain the polymers having the polyorganosiloxane unit in the side chain. The adhesive strength at the boundary is obtd., if the graft polymer having the polyorganosiloxane in the branch polymer is used in the ink repulsive layer and further the graft polymer having the polyorganosiloxane in the branch polymer is incorporated into the photosensitive layer in such a manner. In addition, the production is facilitated and the coating property is improved.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention uses a polymer having polyorganosiloxane units in its side chains in the ink repellent layer, and also uses a polymer having polyorganosiloxane units in its side chains in the photosensitive layer. The present invention relates to positive-working and negative-working photosensitive lithographic printing plates that do not require dampening water and contain the following.

(Prior Art) Many photosensitive lithographic printing plates that do not require dampening water have been proposed, which are comprised of a substrate, an ink repellent layer provided on the substrate, and a photosensitive layer provided on this layer.

Among these known techniques, regarding a positive type photosensitive lithographic printing plate that does not require dampening water and uses a photosensitive layer containing an orthoquinone diazide compound together with a novolak resin, epoxy resin, acrylic resin, etc., Japanese Patent Publication No. 55-47383, Japanese Patent Publication No. 61-613, Japanese Patent Application Publication No. 56-25740
It is stated in the No. Further, examples include a negative-working photosensitive lithographic printing plate I plate that does not require dampening water and a negative-working photosensitive planographic printing plate that does not require dampening water and whose photosensitive layer is formed from a photopolymerizable composition, and a negative-working photosensitive lithographic printing plate that does not require dampening water and uses a diazo resin. Are known. (Tokuko Sho 47-236
(See Publication No. 1) (Problems to be solved by the invention) However, the printing plates shown in these
In both cases, silicone having a siloxane bond as the main chain is used as the ink repellent layer, and a photosensitive layer having low affinity with silicone must be laminated, making it difficult to manufacture.

For example, Japanese Patent Publication No. 55-47383 discloses a method of manufacturing a photosensitive layer coated on a polyolefin film by pressing it onto a support provided with a silicone layer. However, it is extremely difficult to manufacture industrially using such a method.

In addition, since photosensitive layers having low affinity with silicone are laminated, there is a problem that the adhesive force at the interface between the two layers is insufficient, making it difficult to obtain a good image.

For these reasons, it has been desired to have an ink repellent layer that has a strong affinity with the photosensitive layer and has sufficient adhesive strength at the interface between the two layers. On the other hand, there has been a desire for a photosensitive layer that has high affinity with the ink repellent layer, can be easily coated on the ink repellent layer, has a contact force at the interface, and has good ink adhesion.

(Means for Solving the Problems) The sweat of the present invention can be used in photosensitive lithographic printing plates that do not require dampening water and have a strong affinity between the photosensitive layer and the ink repellent layer and sufficient adhesion between the two layers. As a result of extensive research into an ink repellent layer that can be easily applied, a photosensitive layer that has adhesive strength at the interface, and has good ink adhesion, we have developed an ink repellent layer with polyorganosiloxane units in side chains. We have learned that the above object can be achieved by using a graft polymer having polyorganosiloxane units in the side chain (technical polymer) and also by incorporating a graft polymer having a polyorganosiloxane unit in the side chain (technical polymer) in the photosensitive layer. We have arrived at the present invention. That is, the gist of the present invention is a photosensitive lithographic printing plate that does not require dampening water and has an ink repellent layer and a photosensitive layer provided in this order on a substrate, wherein the ink repellent layer and the photosensitive layer are made of polyorganosiloxane. The present invention relates to a photosensitive lithographic printing plate that does not require dampening water and is characterized by containing a polymer having units in side chains.

The present invention will be explained in detail below.

The photosensitive lithographic printing plate that does not require dampening water of the present invention has a photosensitive layer serving as an ink repelling layer and an ink receiving layer in this order on a substrate.

The substrate is flexible enough to be set on a regular lithographic printing machine,
There is no particular restriction as long as it can withstand the load applied during printing. Examples include papers such as coated paper, metal plates such as aluminum plates, and plastic films such as polyethylene terephthalate. It is also useful to provide antihalation layers on these substrates.

The polymer used in the ink repellent layer and photosensitive layer of the present invention is a polymer having the following general formula (a graph having a repeating unit as shown by +>) in the side chain (technical polymer).

−4-3i-0→−・・・・・・・・・(I) Here R
1. RZ is each arbitrarily selected from a hydrogen atom, an unsubstituted or substituted (for example, by a halogen atom, cyano group, or amino group) methyl group having 1 to 10 carbon atoms, an alkyl group, an alkenyl group, or a phenyl group. . The molecular weight of the branched polymer is arbitrary, but preferably the number average molecular weight f
f1 (GPC method, polystyrene conversion) is 100 to 10.
000, particularly preferably in the range of 500 to 7,000.

Such graft polymers can be used, for example, in [Kobunshi Paper 'J
”Vo 1. 43. No, 11. P, 74
1 (1986), by copolymerizing a macro[I monomer having a polymerizable functional group at the end of a polyorganosiloxane and a monomer copolymerizable with it (macro-sevenmer method). I can do things.

When used in radical polymerization, the terminal polymerizable functional group of the macromonomer of polyorganosiloxane includes, for example, a methacryloyl group, an acryloyl group, a crotonoyl group, an isocrotonoyl group, an oleoyl group, and the like. Preferred are methacryloyl group, acryloyl group, and crotonoyl group.

In addition, when polymerizing with polyester or polyamide, examples of the terminal polymerizable functional group include a hydroxyl group, a dihydroxyl group, and a carboxylboxyl group.

In the present invention, polyorganosiloxane units are placed on the side in
The copolymerizable component of the main chain (backbone polymer) of the graft polymer in (technical polymer) is a monomer that can be copolymerized with the above-mentioned macromonomer.

In particular, as monomers for radical polymerization constituting these main chains, the following compounds having unsaturated bonds are used.

(+) Monomers having a hydroxyl group: 2-hydroxyethyl (meth)acrylate (acrylic and methacrylic types are collectively referred to as (meth)acrylate, etc., hereinafter the same), 2-hydroxypropyl (meth)acrylate, 2-hydroxypentyl (meth)acrylate, 4
- (meth)acrylate monomers such as hydroxyphenyl (meth)acrylate, 2-hydroxyphenyl (meth)acrylate, N-methylol (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-(hydroxyphenyl)(meth) ) Acrylamide, (meth)acrylamide monomers such as N-(hydroxynaphthyl)-(meth)acrylamide, 0-1m-
1p-Hydroxystyrene monomers, etc. (2) (Meth)acrylic acid ester or amide monomers other than (+); Methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)
Alkyl (meth)acrylates such as acrylate, N
-Phenyl (meth)acrylamide, 0-1m-1p-
Methoxyphenyl (meth)acrylamide, 0-1m-
2p-Ethoxyphenyl (meth)acrylamides (3) Monomers having a cyano group in the side chain: (meth)acrylonidonitrile, 2-pentenitrile, 2-methyl-3-butenenitrile, 2-cyanoethyl acrylate, 0- 5m-1p-cyanostyrene, etc. (4) Chimers having carboxylic acid in the side chain: (meth)
Acrylic acid, itaconic acid and its anhydride, maleic acid and its anhydride, crotonic acid, etc. (5) Vinyl ethers: Probyl vinyl ether, butyl vinyl ether, octyl vinyl ether, phenyl vinyl ether, etc. (6) Styrenes: α-methylstyrene, Methylstyrene, chloromethylstyrene, styrene, etc. (vinyl ketones: methyl vinyl ketone, ethyl vinyl ketone, propyl vinyl ketone, etc. (8)) Monomers other than (1) to (7): ethylene, propylene, isobutylene, butadiene, chloride Examples include olefins such as vinyl, N-vinylpyrrolidone, N-vinylcarbazole, 4-vinylpyridine, etc.
Other monomers that can undergo radical copolymerization with these monomers may be used. In the present invention, the above (]
), (2), (3) and/or (4) are preferred.

Although specific monomers have been listed as constitutional units of the main chain (stem polymer) component, the present invention is not limited to those listed above, and other types of monomers may be used depending on the case.

In the above graft polymer, preferable examples of the structural unit having a polyorganosiloxane unit in the side chain include:
Examples include those represented by the following general formula (2).

1← CF■2-C→-・・・・・・・・・ (2)C
-0 In the formula, R3, R', R6 and R7 are each a hydrogen atom,
It represents an alkyl group (methyl group, ethyl group, etc.) or a halogen atom, and R' is a linking group, for example, a cycloalkylene group (
cyclohexylene group, etc.), arylene group (phenylene group, tolylene group, naphthylene group), alkylene group (alkylene group having 1 to 5 carbon atoms, etc.), and n represents an integer of 2 or more.

Further, preferable structural units constituting the copolymer with the above structural units include those represented by the following formulas (3) and/or (4).

Ra [1← CH, -C publication- ・・・・・・・・・ (3) C=0 IO −←CH, −C→−・・・・・・・・・ (4) N In the formula, R# and R1G each represent a hydrogen atom or an alkyl group (especially preferably a methyl group or an ethyl group),
R9 is a hydroxy group, an alkoxy group (especially a methoxy group,
Ethoxy is preferred) or represents an oxy or alkoxy group. ) is shown.

When used in the ink repellent layer, the proportion of each of these structural units in the copolymer is such that the structural unit represented by (2) is 5 to 70% by weight, preferably 5 to 60% by weight;
3) The structural unit represented by formula (4) is 0 to 80% by weight, or 10 to 60% by weight, and the structural unit represented by formula (4) is 0% by weight.
Those in the range of ~95% by weight, preferably 10-85% by weight are preferred.

When used in the photosensitive layer, the structural unit represented by formula (6) is 0.1 to 50% by weight, preferably 0.3 to 2.
0% by weight, the structural unit represented by the formula (force) is 0 to 99.9% by weight, preferably 10 to 99% by weight, the structural unit represented by the formula (8) is 0 to 80% by weight, preferably, 10-6
A range of 0% by weight is preferred.

In addition to the above-mentioned graft polymers used in the photosensitive layer, a graft polymer using a macromonomer having polyalkyl (meth)acrylate in the side chain may also be used. Examples of such macromonomers include terminal polymerizable functional groups such as methacryloyl, acryloyl, crotonoyl, isocrotonoyl, and oleoyl groups, and side chains (technical polymers) such as polyethyl (
Examples include polyalkyl (meth)acrylates such as meth)acrylate, polypropyl (meth)acrylate, and polybutyl (meth)acrylate. The number average molecular weight of these macromonomers is 500 to 80.
A range of 00 is preferred.

- The molecular weight of the graft polymer used in the ink repellent layer and the photosensitive layer is: -Finally, the weight average molecular weight measured by a known gel permeation chromatography method is 10,000 to 1,000,000, preferably 50,000 to 1,000,000. 600,000 range is used.

The ink repellent layer is formed by dissolving the graft polymer in a solvent and applying it onto the substrate. Coating solvents include cellosolves such as methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, and ethyl cellosolve acetate, carpitols such as methyl calpitol and ethyl carpitol, dimethyl formamide, dimethyl sulfoxide, dioxane, acetone, and methyl ethyl ketone. , cyclohexanone, trichlorethylene and the like. As the coating method, conventionally known methods such as spin coating, wire bar coating, dip coating, air knife coating, roll coating, blade coating, and curtain coating can be used.

The thickness of the ink repellent layer is selected from the range of 0.3 μm to 15 μm, preferably 0.6 μm to 10 μm.

The photosensitive layer of the present invention contains the above graft polymer and a photosensitive substance. As the photosensitive material, both positive and negative types can be used.

Examples of orthoquinone diazide compounds that can be used in positive type photosensitive lithographic printing plates that do not require dampening water include polycondensation resins of phenols and aldehydes or ketones tn, and orthoquinonediazide compounds represented by the following formula (5) or (6). Examples include orthoquinonediazide sulfonic acid esters or carboxylic acid esters obtained by chemically condensing quinonediazide sulfonic acid or carboxylic acid derivatives.

(In the formula, X is a group represented by -3○2Y or -COY,
Y means a group that can be removed during condensation, such as a halogen atom or an alkali metal. ) Specific examples of the compounds expressed in -ritual (5) above are:
1,2-benzoquinonediazide (2)-4-sulfonyl chloride, 1,2-benzoquinonediazide (2)-4-
Carbonyl chloride, 1,2-benzoquinone diazide (
2) -5-sulfonyl chloride, 1°2-benzoquinonediazide (2)-5-carbonyl chloride, and the like. Specific examples of compounds represented by formula (6) above include 1,2-naphthoquinonediazide (2)-4-sulfonyl chloride, 1,2-naphthoquinonediazide (2)
-4-carbonyl chloride, 1,2-naphthoquinonediazide (2)-5-sulfonyl chloride, 1,2-naphthoquinonediazide (2)-5-carbonyl chloride, and the like.

Examples of polycondensation resins of phenols and aldehydes or ketones include polycondensates of pyrogallol and acetone as described in Japanese Patent Publication No. 43-28403, and polycondensates of pyrogallol and acetone as described in Japanese Patent Publication No. 55-76346. As described in Japanese Patent Publication No. 45-9610, a polycondensate of a mixture of pyrogallol and resorcin and acetone, phenol formaldehyde novolac resin or meta-cresol formaldehyde novolac resin, Japanese Patent Publication No. 1983-9610. δ8 in Publication No. 5083
Particularly substituted phenol/formalin resins (e.g. baracresol/formalin resin, rose-substituted phenol/formalin resin)
t-butylphenol/formalin resin, rosethylphenol/formalin resin, rosepropylphenol/
Formalin resin, rose isopropylphenol formalin 84 JJif, rose n-butylphenol formalin resin, rose octylphenol formalin resin, etc.) As described in Japanese Patent Publication No. 62-60407, an alkyl group having 3 to 12 carbon atoms. or phenyl group-substituted phenol and phenol or its methyl substituted product or a mixture thereof in a molar ratio of 1:9 to 9;1
Polycondensates of formaldehyde and mixtures of phenols containing (for example, polycondensates of the above-mentioned rose-substituted phenol and phenol, vala-cresol, metacresol, or octocresol), and the like.

The ester ratio of orthoquinonediazide groups to hydroxyl groups in the polycondensation resin of phenols and aldehydes or ketones is preferably 15 to 100 mol%, more preferably 20 to 80 mol%.

Further, other orthoquinonediazide compounds include orthonaphthoquinonediazide sulfonic acid esters of polyhydroxybenzophenone (for example, 12-naphthoquinonediazide (2)-5-sulfonic acid ester, 1,2-naphthoquinonediazide (2)-4-sulfonic acid ester, etc.) ) etc.

This polyhydroxybenzophenone is a compound obtained by substituting two or more hydrogen atoms of benzophenone with hydroxyl groups, such as dihydroxybenzophenone, trihydroxyhensiphenone, tetrahydroxybenzophenone, pentahydroxybenzophenone, octahydroxybenzophenone, or a derivative thereof ( For example, substituents of halogen atoms, alkyl groups, aryl groups, aralkyl groups, and carboxylic acid groups may be mentioned. Preferably, it is 1-dihydroxybenzophenone or tetrahydroxyhensiphenone, and more preferably 2°3.4-)dihydroxybenzophenone and 2,3°4.4'-tetrahydroxybenzophenone.

The esterification rate for hydroxyl groups is preferably 30 to 100%.

As the orthoquinonediazide compound used in the present invention, each of the above compounds may be used alone, or two or more thereof may be used in combination.

Among these orthoquinonediazide compounds listed above, 2,3. i) 1,2 of dihydroxybenzophenone
- Naphthoquinonediazide (2) -5-sulfonic acid ester or 1,2-naphthoquinonediazide (2) -4-sulfonic acid ester, 1,2-naphthoquinonediazide (2) of metacresol formaldehyde novolak resin
)-5-sulfonic acid ester or 1,2-naphthoquinone diazide (2)-4-sulfonic acid ester, or
Mixtures of these are more preferred.

The proportion of the orthoquinonediazide compound in the photosensitive layer is usually 5 to 60% by weight, preferably 20 to 50% by weight.

Conventionally known diazo compounds can be used as appropriate for the negative type photosensitive lithographic printing plate that does not require dampening water.
Included are diazo resins represented by condensates of aromatic diazonium salts and, for example, active carbonyl-containing compounds, especially formaldehyde, among which diazo resins soluble in organic solvents are preferred.

Preferred specific examples of the diazo resin include resins having a molecular weight of about 500 to 10,000 represented by the following formula (7).

In the formula R, R12, R11 and RI4 each represent a hydrogen atom, an alkyl group or an alkoxy group, preferably a hydrogen atom, and RI5 represents a hydrogen atom, an alkyl group or a phenyl group, preferably not a hydrogen atom.

X in the formula represents a counter anion of the diad resin, specifically, organic carboxylic acids such as PF6, BF, decanoic acid, benzoic acid, organic phosphoric acids such as phenylphosphoric acid, and sulfonic acids such as methanesulfonic acid. etc.

Y in the formula represents NH, S, and O. Furthermore, Z in the formula is at least one selected from sulfonic acid group, sulfonate (Na salt, KJi, etc.), 1, sulfine group, sulfinate (Na salt, K salt, etc.) group, OHI, C00flfi. Indicates a phenylene group or naphthylene group substituted with the above direct substituent. The 81j combination of m and n has a molar ratio of m/n = l 10 to 10, preferably I1
Indicates a range of 0 to 2.

Note that the constituent units in brackets [ ] are written as in (7) simply to indicate the respective abundances, and do not need to exist collectively.

The content of diazo resin in the photosensitive layer is preferably 1 to 70
% by weight, more preferably from 3 to 60% by weight.

In the present invention, the binder resin that can be used in combination with the graft polymer containing polyorganosiloxane as a technical polymer may be used in the case of positive type, for example, JP-A-63-5
These include novolak resins as described in Japanese Patent Application No. 6650, acrylic resins as described in Japanese Patent Application Laid-Open No. 62-279324, and the like. In the case of a negative type, for example, acrylic resin as described in Japanese Patent Application Laid-Open No. 62-59947, polyester resin as described in Japanese Patent Publication No. 57-20614, polyamide, etc. can be used.

Containment of these polymer compounds when a graft polymer containing polyolkalisiloxane as a polymer is used alone as a binder or when mixed with other binder resins (for example, acrylic resin, novolak resin, polyester, polyamide, etc.) The amount is 30 to 99 weight %, particularly preferably 40 to 97 weight %, in the photosensitive layer, whether it is a positive type or a negative type.

In addition, graft polymers using polyorganosiloxane as a technical polymer and other binder resins (such as acrylic resins, novolanc resins, polyesters, polyamides, etc.)
When used in combination with other binder resins, the ratio of the graft polymer to other binder resins is 99% by weight or less, particularly preferably 0.1 to 70% by weight.

In addition to the materials described above, the photosensitive layer of the photosensitive lithographic printing plate that does not require dampening water of the present invention may contain dyes, pigments, coatability improvers, plasticizers, Agents, oil sensitizers, stabilizers, etc. can be added.

It is advantageous that the photosensitive layer of the positive type photosensitive lithographic printing plate that does not require dampening water further contains a known exposure-visible image imparting agent.

Examples of the above dyes include Victoria Pure Blue B OH, Oil Blue #603, and Oil Pink #31.
2. Patent pure blue, crystal violet,
Leuco Crystal Hiolet, Brilliant Green, Ethyl Violet, Methyl Green, Erythrosin B1 Basic Tsuksin, Malachite Green, Leucomalachite Green, m-Gresol Bubbles, Cresol Red, Xylenol Blue, Rhodamine B, Auramine, 4-p-diethylaminophenyl Examples include triphenylmethane-based, diphenylmethane-based, oxazine-based, xanthine-based, iminonaphthoquinone-based, azomethine-based, and anthraquinone-based dyes represented by iminonaphthoquinone, cyano-p-diethylaminophenyl acetanilide, and the like.

The dye is generally contained in the photosensitive layer in an amount of about 0.01 to about 10% by weight, preferably about 0.05 to 8% by weight.

Examples of the coating property improver include alkyl ethers (eg, ethyl cellulose, methyl cellulose), fluorine-based surfactants, and nonionic surfactants (eg, Pluronic L-64 (manufactured by Asahi Denka)).

Examples of plasticizers for imparting flexibility and abrasion resistance to coating films include butylphthalyl, polyethylene glycol,
Examples include tributyl citrate, dibutyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, tricresyl phosphate, tributyl phosphate, trioctyl phosphate, tetrahydrafurfuryl oleate, oligomers of acrylic acid or methacrylic acid, etc. .

As a liposensitizing agent for improving the liposensitivity of the image area, there may be mentioned, for example, a half ester of a styrene-maleic anhydride copolymer with alcohol described in JP-A-55-527.

Furthermore, various liposensitizing agents having hydrophobic groups, such as p-octylphenol-formalin novolak resin, p-butylphenol-formalin novolak resin, p-L-
Modified novolak resins such as butylphenol benzaldehyde resin, rosin modified novolak resin, 0-naphthoquinonediazide sulfonic acid ester (ester of OH7f5 ([20 to 70 mol%
) etc. can be added.

Examples of stabilizers include polyacrylic acid, tartaric acid, phosphoric acid, phosphorous acid, organic acids (acrylic acid, methacrylic acid,
citric acid, oxalic acid, benzenesulfonic acid, naphthalenesulfonic acid, 4-methoxy-2-hydroxybenzophenone-5-sulfonic acid, etc.).

The amount of these additives added varies depending on the purpose of use, but is generally 0.01% to 30% by weight based on the total solid content.
Weight percent is preferred.

The photosensitive layer of the positive type photosensitive lithographic printing plate that does not require dampening water may further contain a known exposure-visible image imparting agent.
The exposure visible image imparting agent is a compound that generates an acid upon exposure to form a salt with a dye.

As the compound that generates acid upon exposure to light, trihaloalkyl compounds represented by the formula below are preferred.

(However, X is a trihaloalkyl group having 1 to 3 carbon atoms, Wl is N or P, Wz is O, S or Se, and W3 cyclizes w' and Wl and forms a chromophore. ) Specific compounds include oxadiazole compounds having a benzofuran ring such as OCR,1;
2-trichloromethyl-5-(p-methoxystyryl)-1, which is described in JP-A-54-74728,
Examples include 3,4-oxadiazole compounds.

Also, 4-(2,4-dimethoxy-4-styryl)-6-1- described in JP-A No. 53-36223
Dichloromethyl-2-pyrone compound, 24-bis-(trichloromethyl)-6-p-methoxystyryl-5-)
Riazine compound, 2゜4-bis-(trichloromethyl)
-6-p-dimethylaminostyryl-8-triazine compound and the like.

The amount of the exposed visible image imparting agent added is preferably 0.0120% by weight in the photosensitive layer, more preferably 0.1 to 10% by weight.
Weight%.

The photosensitive layer is coated by dissolving each of the above components in a solvent. Solvents that can be used include cellosolves such as methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, and ethyl cellosolve acetate, carpitols such as methyl calpitol and ethyl carpitol, dimethylformamide, dimethyl sulfogide, and dioxane. , acetone, methyl ethyl ketone, cyclohexanone, trichloroethylene and the like. These solvents may be used alone or in combination of two or more. However, use a solvent that does not dissolve the ink repellent layer as much as possible. The coating method is a conventionally known method, such as spin coating, wire spray coating,
Dip coating, air knife coating, roll coating, blade coating, curtain coating, etc. are possible. After coating, the coating film is sufficiently dried to obtain a photosensitive lithographic printing plate that does not require dampening water.

At that time, the thickness of the photosensitive layer is 0.1 to 108 m, preferably 1 to 8 m.

Conventional methods can be applied to plate-making the photosensitive lithographic printing plate that does not require dampening water of the present invention obtained as described above. That is, a relief image is obtained by exposing the transparent original image having a line image, halftone image, etc. to light, and then developing it with an aqueous developer. A suitable light source for exposure is 180n
Any general-purpose light source including ultraviolet rays and visible rays of m or more may be used, but carbon arc lamps, mercury lamps, xenon lamps, methyl halide lamps, strobes, etc. are particularly preferred.

The developer used in the development of the dampening water-free photosensitive lithographic printing plate of the present invention may be any known developer, but in particular, in a positive-working dampening water-free photosensitive lithographic printing plate, polyorganosiloxane units are When a graft polymer having a chain (branch polymer) is mixed with a novolak resin, development can be performed using an alkaline aqueous solution (described later) that does not contain an organic solvent. In other cases, it is preferable to use a mixture of a specific organic solvent with an alkaline aqueous solution. Here, the specific organic solvent is a solvent that dissolves or swells the non-image area of the photosensitive layer when contained in the developer. It refers to an organic solvent that can be used as an organic solvent and has a solubility in water of 10% by weight or less at room temperature. Such organic solvents only need to have the above-mentioned characteristics. Specifically, carboxylic acid esters such as ethyl acetate, propyl acetate, butyl acetate, amyl acetate, benzyl acetate, ethylene glycol monobutyl acetate-1-1 butyl lactate, butyl levulinate, ethyl butyl ketone,
Ketones such as methyl isobutyl ketone and cyclohexanone, alcohols such as ethylene glycol monobutyl ether, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, hensyl alcohol, methylphenyl carbinol, n-amyl alcohol, and methyl amyl alcohol, xylene and halogenated hydrocarbons such as methylene dichloride and monochlorobenzene. One or more of these organic solvents may be used. Ethylene glycol monophenyl ether and benzyl alcohol are particularly effective. The content of these organic solvents in the developer is approximately 1 to 20% by weight, particularly preferably 2 to 10% by weight.

Certain solubilizers may also be included to aid in the solubility of these organic solvents in water. Such solubilizers include those that are more water soluble than the above-mentioned organic solvents,
It is better to use low molecular weight alcohols and ketones. Furthermore, anionic activators, amphoteric activators, etc. can also be used. Examples of such alcohols and ketones include methanol, ethanol, propatool, acetone, methyl ethyl ketone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methoxybutanol, ethoxybutanol, 4-methoxy-methylbutanol, N-methylpyrrolidone, etc. It is preferable to use Preferred examples of the activator include sodium isopropylnaphthalene sulfonate, sodium n-butylnaphthalene sulfonate, sodium N-methyl-N-pentadecyl aminoacetate, and sodium lauryl sulfate. The content of these solubilizers is preferably 30% by weight or less.

On the other hand, the alkaline substances contained in the developer include (A) sodium silicate, potassium silicate, potassium hydroxide, sodium hydroxide, lithium hydroxide, sodium or ammonium salts of secondary or tertiary phosphoric acid; , sodium metasilicate, ammonia, etc. (B) Mono, di or trimethylamine, mono, di or triethylamine, mono or diisopropylamine, n-butylamine, mono, di or triethanolamine, mono, di or l-li isoprobanolamine,
Examples include organic compounds such as ethyleneimine and ethylenediamine.

Preferred are (A) sodium silicate and potassium silicate, and (B) organic amine compounds.

Particularly preferred are potassium silicate and di- or triethanolamine.

The content of these alkaline agents in the developer is usually 0.
．． 0.5 to 8% by weight, preferably 0.5 to 6% by weight.

Further, in order to improve storage stability and the like, it is preferable to include a water-soluble sulfite salt in the developer as necessary. Such water-soluble sulfite salts are preferably alkali or alkaline earth metal salts of sulfite, such as sodium sulfite, potassium sulfite, lithium sulfite, and magnesium sulfite. The content of these sulfite salts in the developer is usually 0.05 to 4% by weight, preferably 0.01 to 4% by weight.
It is 1 to 1% by weight.

After imagewise exposure, the photosensitive lithographic printing plate which does not require dampening water of the present invention can be exposed to light after 10 to 60 seconds at about 10°C to 40°C by contacting it with the above-mentioned developer or rubbing it. teeth,
The photosensitive layer in the non-image area is completely removed without adversely affecting the image area of the photosensitive layer.

(Examples) The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.

(Synthesis example of polyorganosiloxane macromonomer) α, ω-dihydroxydimethylpolysiloxane H3 1 (04S t O→, H with an average of 50 CH)
.

220g (0.1 mol) and 9.49g (0°1 mol) of pyridine
2 mol) of diethyl ether 400mf! , melted into? 10% of 12.06 g (0.05 mol) of T-methacryloxypropylmethyldichlorosilane to Ij t&
A diethyl ether solution was gradually added dropwise at room temperature over 1 hour.

The reaction proceeded immediately and white crystals of pyridine hydrochloride were precipitated. After the addition was completed, the mixture was further stirred at room temperature for 1 hour, and the crystals of pyridine hydrochloride were removed by filtration. Next, this oral mixture was placed in a separatory funnel, and 500 mj2 of water was added thereto, shaken well, and washed with water. After washing with water, the separatory funnel was left standing to separate the upper ether layer and the lower aqueous layer, and anhydrous sulfate was added to the obtained ether layer, which was then left overnight at room temperature to dehydrate.

Thereafter, anhydrous sulfate was removed by filtration, and the resulting solution was distilled under reduced pressure to remove ether, yielding 225 g of organopolysiloxane macromonomer.

(Synthesis example of graft polymer for ink repellent layer) Polyorganosiloxane macromonomer synthesized in the above synthesis example (
M~1: The terminal polymerizable functional group is a methacryloyl group, and the organopolysiloxane is dimethylpolysiloxane with a number average molecular weight of about 5,000. ) and each monomer shown in Table 1 below in the proportions shown in Table 1 to synthesize a graft polymer.

(The symbols in the NAME column in Table 1 are the common names given to the synthesized graft polymers. Also, AN is acrylonitrile, MA is methyl acrylate,
Ph and MA represent N-phenylmethacrylamide, and M-1 represents polydimethylsiloxane macromonomer.

Furthermore, the column labeled Mw shows the weight average molecular weight of the synthesized polymer compound. ) Under a nitrogen stream, each component and 1.5 mol% of abbisisobutyronitrile (AIBN) were dissolved in methyl ethyl ketone in an amount of 1.5 times the total weight of each component shown in Table 1, and this mixed solution was dissolved. The mixture was heated at 60°C for 6 hours while stirring. After completion of this reaction, 1,4-dioxane as a coating solvent was added and solvent replacement was performed by distillation under reduced pressure. 90 more after that
Reflux was performed at °C for 1 hour.

(Synthesis example of graft polymer for photosensitive layer) Polyorganosiloxane macromonomer synthesized in the above synthesis example (M-1
), polybutyl acrylate macromonomer (M-2)
(manufactured by Toagosei Co., Ltd., AB-6) and each of the seven polymers shown in Table 2 below were used in the proportions shown in Table 2 to synthesize a graft polymer.

(The symbols in the NAME column in the table are the common names given to the synthesized graft polymers. In addition, the symbols already listed in Table 1 are the same, and EA is ethyl acrylate, MAA is methacrylic acid, M- 2 indicates polybutyl acrylate macromonomer. Furthermore, the column indicated by Mw indicates the weight average molecular weight of the synthesized polymer compound.) Total weight of each component shown in Table 1 under nitrogen stream. Each component and 1.5 mol% of azobisisobutyronitrile (AIBN) were dissolved in 1.5 times the weight of methyl cellosolve, and the mixed solution was heated at 60"C for 6 hours while stirring. did.

After completion of this reaction, methylcellosolve, a coating solvent, was added and solvent replacement was performed by distillation under reduced pressure. After that, 90°C
The mixture was refluxed for 1 hour.

Further, Table 3 shows the composition of the binder resin used by mixing the above-mentioned organopolysiloxane with a graft polymer having the technical polymer. Furthermore, these binders were used as a comparative example to test the effectiveness of the present invention by attempting to coat them on a silicone rubber layer without mixing them with a graft polymer containing organopolysiloxane as a technical polymer. .

Examples 1 to 9 Photosensitive solutions were prepared as follows using the various binders described above.

(a) Positive type photosensitive liquid (b) Front negative type photosensitive liquid *2: Hexafluorophosphate of a polycondensate of p-diazophenylamine and paraformaldehyde, this diazo resin undergoes a polycondensation reaction with β-naphthol Weight average molecular weight as a product: 12,800° Type *1: 1° 2-naphthoquinonediazide-5-sulfonic acid ester of pyrogallol/acetone polycondensate (esterification rate: 30%).

Mw=1.500) Table 4 Negative type In Tables 3 and 4 above, A-1, A-2 and N-1
represents a copolymer of each of the heptads shown in Table 5 below.

Table (The symbols in the NAME column in Table 5 are the common names given to the synthesized polymer compounds.Other symbols are the same as in Table 2, and in the Mw column, It shows the weight average molecular weight of the synthesized polymer compound.However, N-1 is a novolac resin, the composition is phenol, m-cresol, p-2 resol, and the composition ratio is 20:48:32 in molar ratio. (The weight average molecular weight is 4800.) (Production of a photosensitive lithographic printing plate that does not require dampening water) The graft polymer for the ink repellent layer shown in Table 1 synthesized in the above synthesis example was added in an amount of 800 parts based on the solid content of the polymer. The solution was dissolved in 1,4-dioxane and coated on a 0.3mm aluminum plate using a spin coating machine at 60°C and 150 rpm. then 8
It was dried at 5°C for 3 minutes to form an ink repellent layer.

Apply the photosensitive liquid onto the ink repellent layer using a spin coater,
Coating was carried out at 0°C and 150 rpm. Thereafter, it was dried at 85° C. for 3 minutes to produce a photosensitive lithographic printing plate that did not require dampening water.

After coating, the state of coating of the photosensitive layer on the ink repellent layer and the adhesive strength between the ink repellent layer and the photosensitive layer were evaluated.

The results are shown in Tables 6 and 7. Uncoating means that no photosensitive layer could be coated on the ink repellent layer.

Also, "coatable" means that the photosensitive layer was coated evenly and uniformly over the entire surface of the ink repellent layer. Adhesive strength was evaluated by peeling off the tape.

Regarding the photosensitive lithographic printing plate that did not require dampening water and could be coated in the evaluation of coatability, it was
The ink receptivity of the image area and the ink repulsion of the non-image area were evaluated by exposing to light from a distance of 0 cm, developing, and performing actual printing.

The developer used was the following developer solution-1 except for the one using binder N-1 (novolac resin). In the case of a positive type, the developing method was carried out by dipping the following developing solution 1 12 times diluted with water at 25° C. for 20 seconds, and then washing with water. In the case of a negative type, the sample was immersed for 40 seconds at 25 DEG C. in a 4-fold dilution of the following developer solution 1 with water, and then washed with water.

Those using binder N-1 (novolac resin) are 5D
Development was carried out by immersing R-1 (manufactured by Konica ■) developer diluted 6 times with water at 25°C for 40 seconds and then washing with water.

(Composition of developer-1) Benzyl alcohol 50g Triethanolamine 15g Sodium sulfite 5g Sodium butylnaphthalene sulfonate 25g Water
500g printing is done by Sun.
The test was carried out using Offset 220E (manufactured by San Printing Machinery ■) without supplying dampening water.

The ink used was Toyo King Ultra TKU Aquares G ink (manufactured by Toyo Ink Manufacturing ■). Tables 6 and 7 show the results of evaluating the ink receptivity in the image area and the ink repulsion in the non-image area on the printed matter.

The quality of the ink repulsion in the non-image area was judged based on whether the printed matter had scumming or not. In addition, the ink receptivity of the image area was indicated by the number of sheets of waste paper.

(Effects of the present invention) As explained in detail above, the graft polymer having the organopolysiloxane of the present invention as a technical polymer is used in the ink repellent layer, and the photosensitive layer also has an organopolysiloxane as a technical polymer. If a graft polymer is included, a photosensitive lithographic printing plate that has good adhesion at the interface, good ink adhesion, is extremely easy to manufacture, and has good coating properties and does not require dampening water can be obtained. The effect is produced. Therefore, the present invention is extremely useful industrially.

Claims (1)

[Claims] A dampening water-free photosensitive lithographic printing plate having an ink repellent layer and a photosensitive layer provided in this order on a substrate, the ink repellent layer and the photosensitive layer comprising a polymer having polyorganosiloxane units in side chains. A photosensitive lithographic printing plate that does not require dampening water.